Platelet-Based Markers Associated With Vascular Access Dysfunction in Hemodialysis Patients.

Introduction Vascular access (VA) dysfunction is a major determinant of inadequate dialysis delivery and clinical complications in hemodialysis (HD) patients. Mean platelet volume (MPV), a marker of platelet activation, has emerged as a potential discriminatory marker for thrombotic events and VA complications. The aim of this study was to evaluate the association and discriminatory performance of platelet indices, particularly MPV, in identifying VA dysfunction in patients undergoing chronic HD. Secondary objectives included exploring the relationship of platelet parameters with dialysis adequacy and selected hematologic parameters. By evaluating the discriminatory performance of these routinely available platelet indices, this study also explored their potential clinical relevance as accessible biomarkers that may help identify VA dysfunction in HD patients. Materials and methods This retrospective study analyzed 104 HD patients treated between 2017 and 2021. Patients were grouped by VA: arteriovenous fistula (AVF, n=51) or permanent catheter (PC, n=53). MPV and platelet count (PLT) were evaluated against access dysfunction (Qb<250 mL/min), dialysis adequacy indices (single pool (spKt/V), urea reduction ratio (URR%)), and anemia control parameters (hemoglobin (Hgb) levels; erythropoiesis-stimulating agents (ESAs) doses used). Correlation and comparative analyses, effect size estimation, and receiver operating characteristic (ROC) curve analysis were performed. MPV was higher in PC patients (11.34±1.09 fL) than AVF patients (10.11±1.33 fL; p<0.00001). Higher MPV correlated with lower spKt/V, lower Qb, higher ESA requirements, and lower Hgb in both groups (p<0.001). ROC analysis showed excellent discriminatory performance of MPV for identifying VA dysfunction with an AUC of 0.96 (95% CI: 0.904-1.00, p<0.0001) in AVF and an AUC of 0.956 (95% CI: 0.884-1.00; p< 0.001) in PC, with optimal cut-off values >10.27 fL and >11.5 fL, respectively. PLT showed a statistically significant inverse discriminatory ability AUC of 0.053 (95% CI: 0.010-0.096; p<0.001) in AVF and AUC of 0.086 (95% CI: 0.05-0.167; p<0.001) in PC with poor diagnostic performance. Discussion MPV was strongly associated with VA dysfunction in patients undergoing HD. Higher MPV values were linked to reduced dialysis blood flow, lower dialysis adequacy, higher ESA requirements, and lower hemoglobin levels. ROC analysis demonstrated strong discriminatory performance (AUC≈0.96) with clearly identifiable cutoff values across VA types. Although PLT showed a statistical association with VA dysfunction, its inverse discriminatory pattern and lack of a clinically useful threshold limit its practical applicability. The consistent inverse relationship between MPV and PLT supports the potential relevance of platelet activation, rather than platelet quantity, in the pathophysiology of VA dysfunction. Conclusion MPV may represent a readily available laboratory parameter associated with VA dysfunction and dialysis performance in HD patients. Given its routine availability as part of the CBC, MPV may have potential clinical relevance for identifying patients with VA impairment. Prospective studies are needed to validate these findings and to clarify the potential role of platelet indices in VA monitoring.